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fying to their engineer that 2 lbs. must be the greatest difference they will allow between the greatest and least pressures during the Board of Trade tests. This is not an impracticable quantity, for I am willing myself to be confined to one-half of it, but more than this is bad. If on the side of accumulation, it is unsafe, and if on the side of reduced pressure, waste of coal, the interest of the Board of Trade and the shipowner is indissolubly bound up together on this subject, that which is good for one is good for the other, and that which is bad for the one is bad for the other. Herein is wisdom. Let the Board of Trade say, "I will allow no accumulation;" and let the shipowner say, "2 lbs. is the limit I will allow between the greatest and least pressures," during the Board of Trade tests, and the safety of the public and the dividends of steamship companies will be benefited thereby, in addition to which all persons concerned will have peace and comfort.

This brings me now to consider the most wretched and worst of all forms of safety-valve mechanism-the lever and dead weight, this scion of the "evil one" let loose from his chains. He has been stalking through the ranks of engineers enrobed in lamb's clothing, but with the subtlety of the serpent in his heart. This diabolical instrument, this king of boiler bursters, this monster of iniquity, this wholesale murderer, dealing death and destruction to all points of the compass, enshrouded in the cloak of innocence, has been intrusted to guard the most dangerous positions to society, and under the same covering he has been admitted to take part in the deliberations of learned men.

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Fig. 12 shows this piece of mechanism as applied by the president of the Institution of Engineers and Shipbuilders of Scotland. There it stands with its fiendish hand over that hole in the boiler, proclaiming safety to all around, but death and destruction are in its heart. Beguiled by its fair external appearance of respectability, even engineers confide in its promises. But the eye of the thinking man is also upon it, and he sees through its now well-worn and threadbare habiliments, and descries the dry bones within. Let us examine it with its assumed robe of righteousness. Let us follow Mr. Robson, who called several eminent engineers of Glasgow and London to see the performance of this wolf in sheep's clothing in order to force it on to the Board of Trade.

"Oh! wad some power the giftie gie us

To see oursels as ithers see us."

This valve, with the lever and dead weight, was loaded to blow off at 35 lbs. and rose to 46 lbs., closing again at 33 lbs., 31 per cent. of accumulation, difference between the greatest and least pressures, equal to 40 per cent. With the lever and spring at the end of it and the valve loaded to blow off at 35 lbs., under test the pressure rose to 49 lbs., or 40 per cent. of accumulation, and the president of the institution considers this good behaviour, and that no better need be expected or desired by the Board of Trade and Marine Engineers. This valve, containing 17.72 square inches, applied to 19.5 feet of grate, nearly double the size prescribed by the Board of Trade rule.

But this is the valve as seen with his clothes on. Let us unrobe him of his seeming righteousness and dissect the skeleton inside, which lies. hid from the casual, but not from the mental observer. See Fig. 12. V is the valve, fitting in its seat by 4 feathers as shown, and the spindle is cast solid with the valve, both being one casting. C' is the junction of the lever and spindle, and C is the stud which receives the end of the lever, and which is a fixture immovably set in the structure, and with the weight or spring balance attached to the long end of the lever. Let us now get steam up until the pressure is capable of producing motion of the valve. The path of the valve is along the centre line of the seating and spindle, along C' D and is a straight line; while the path of the lever, which is rigidly bound to the valve at C', and rigidly bound to the structure at C, is a radial line C' E about the centre C.

Now I tell Mr. Robson that if the fittings of this valve be good it cannot possibly lift" from its seat, whatever be the pressure beneath it. It is a physical impossibility for it to lift higher from its seat than the play or clearance of the feathers in the seating will allow. The valve will just lift to a height represented by the clearance in the feathers forming the versed line of an arc along C' E, and the semi-chord

of the arc or the line of that portion of the arc C' E, which the clearance in the feathers allows the point C' to pass through, and if the valve be a very good fit in its seating it will not lift at all, but only shoulder up in one side. Because as soon as the play is taken up, the feathers are jambed in the seating, and the greater the power applied at the valve the harder does it jamb. Not all the power on earth could lift this valve. Smash it you can, burst the boiler you may, but lift this valve -never; for jambed it is, firm as the pillars of the universe and durable as the time of the force applied.

Sound aloud, Sir, the death knell of this valve; sign his death warrant, and read the funeral service over his unhallowed grave ere you again lay your head on your pillow to rest, and the blessings of mankind will attend you.

My next will be on the award of the Marine Medal to its President by the Institution of Engineers and Shipbuilders of Scotland for a Paper read in favour of the above wretched valve; also on the "Theory of the Constitution of Steam."

MOLECULAR VORTEX.

The Works of the "Ant" and the "Bee," Manchester.

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NAUTICAL RACE.—A considerable rivalry exists between the two coal exporting ports of Cardiff and Newport. This is not, however, confined to the mere "deadweight" business and extends to other and more "buoyant" projects. At the former place there is an annual pilot-boat regatta held in the Autumn. On the last occasion a Newport boat was fortunate enough to carry off the principal prize, and gave the good town another opportunity of "crowing" over its rival. This could not be borne by any spirited community, and a challenge for £100 a-side was made and accepted, for a race from the Monkstone to Lundy, covering a distance of about 140 miles. The boats matched were the J. N. Knapp, of Newport, and the Anita, of Cardiff. The boats started on the 6th October, at half-past ten o'clock a.m., and returned again on the 7th ; the Anita at about half-past nine o'clock a.m., and the J. N. Knapp at eleven a.m. The tide was thus turned and Cardiff was made happy, and returned to its "black diamond" dealing in peace. The only reason which we have in alluding to the subject is to refer with pleasure to the hardihood and daring of the crews, and as evidencing the fact that there is a nobler ambition than mere money-grubbing existing at these "coaly" places. The race was made in the teeth of a gale of wind from the west, insomuch that half-a-dozen large steamers had taken shelter in Lundy Roads.

EMIGRATION TO SOUTH AMERICA.-No. III.

REPUBLIC OF URUGUAY.

HE Republic of Uruguay, contemplated as a field for European emigration, may, in some respects, be said to equal the Argentine Republic; its climate, although very similar to that of Buenos Ayres, is certainly superior to it, owing to its nearer proximity to the sea. Its physical aspects are more varied and picturesque than the uninteresting pampas of the Argentine; its soil is equally productive, and the whole of its territory, which is about equal in extent to that of England, is suitable for open-air work for Europeans. Geographically, it is situated between the 30th and 35th degree of south latitude, and the 52nd and 58th of west longitude. Its southern coast forms the left bank of the River Plate, at the entrance of which is the City of Monte Video. Its eastern coast is upon the Atlantic; its western is washed by the Uruguay, which, with the River Plate, divides it from the Argentine Republic; and upon the north, it is separated from Brazil by no very remarkable barrier.

Ethnologically, as well as geographically, it is identical with the central provinces of the Argentine Republic, and it was discovered at the same time, in 1515, when it became a Spanish colony. It has since been subject to many vicissitudes, owing to its position as the political buffer betwixt the Spanish and Portuguese races, now represented by the Brazilians and Argentines. The Portuguese made serious and repeated attempts to annex it; in 1679 they founded the City of Colonia upon the River Plate, immediately opposite to that of Buenos Ayres; they also possessed themselves of Monte Video, which they evacuated in 1724. In 1778 they were driven out of Colonia, as it was thought, finally, and the province was made part of the vice-royalty of Buenos Ayres; in 1811 it declared its independence, and in 1814 the Spanish garrison of Monte Video capitulated. It then became one of the united provinces of La Plata, under the name of the "Oriental Province;" in 1815 it seceded and formed itself into an independent republic, which was short-lived, for it was invaded by the Portuguese in 1821 and annexed to that kingdom.

In the same year, upon the independence of Brazil, it was annexed to the Empire under the title of the "Cis-Platina Province." In 1827 the province successfully revolted, and in 1830 proclaimed itself independent, as the "Oriental Republic of Uruguay." In 1839 a war broke out betwixt it and Buenos Ayres, and the Argentine army invaded the country and besieged Monte Video; the siege lasted nine years, and reduced the State to ruin and desolation. In 1865 the revolution of General Flores

resulted in Brazilian intervention; President Aguirre was expelled, and in 1868 General Flores was assassinated, since which period, in common with its sister republics, it has been a prey from time to time to military Condillos. It is they who have furnished an excuse for foreign interventions, sometimes even invited by them; it is they who have ruined the credit of their country; it is they who have turned this garden of South America into a jungle of tigers; and until the Government is sufficiently supported by public opinion to suppress them with inexorable severity, the country will enjoy neither peace nor prosperity at home, nor credit abroad, and emigrants will gradually cease to avail themselves of the great natural advantages possessed in so high a degree by it. Clemency

is doubtless an admirable quality, but justice is a better, and consideration for a criminal is too often indifference to his victim.

But notwithstanding all its trials, and a certain air of provincialism which hangs about it, notwithstanding the great disadvantage of being a small State between two powerful and jealous rivals, it has progressed in a wonderful degree. This is to be attributed to the great attractions which it possesses for emigrants. The capital, Monte Video, the first part at which they touch in the River Plate, is an extremely beautiful town, and although not one half the size of Buenos Ayres, much more likely to encourage people in search of a home to select it. This also applies to the country, which is undulating, well wooded and watered, forming a very favourable contrast to the dreary and timberless pampas of Buenos Ayres. It has also an invaluable superiority over its rival in the quantity of stone abounding in the country for building purposes, or for making roads. Like Buenos Ayres, Monte Video owes its architectural beauty and the floriculture of its quintas to its Italian immigrants, and the decoration of its tasteful shops to the French, who abound in great numbers within the city.

It possesses great commercial advantages, owing to its being placed so near the mouth of the Plata, and although by no means a good port, it is better than that of Buenos Ayres.

In the following statistics, it must be borne in mind, or they will give a false impression, that all vessels "seeking," call at Monte Video, and almost every vessel bound to any other of the ports of the La Plata also call there for a pilot, for orders, or for provisions, and being all registered, as vessels coming to the port, the tonnage returns of Monte Video appear to equal those of Buenos Ayres.

The returns of trade for three years were as follows:

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